Platform LSF Administration Guide Version 6.2
Chapter 18
Resource Allocation Limits
Administering Platform LSF
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Resource allocation limits and resource usage limits
Resource allocation limits are not the same as resource usage limits, which are enforced
during job run time. For example, you set CPU limits, memory limits, and other limits
that take effect after a job starts running. See Chapter 29, “Runtime Resource Usage
Limits” for more information.
How LSF enforces limits
Resource allocation limits are enforced so that they apply to:
◆
Several kinds of resources:
❖
Job slots by host
❖
Job slots per processor
❖
Memory (MB or percentage)
❖
Swap space (MB or percentage)
❖
Tmp space (MB or percentage)
❖
Software licenses
❖
Other shared resources
◆
Several kinds of resource consumers:
❖
Users and user groups (all users or per-user)
❖
Hosts and host groups (all hosts or per-host)
❖
Queues (all queues or per-queue)
❖
Projects (all projects or per-project)
◆
All jobs in the cluster
◆
Combinations of consumers:
❖
For jobs running on different hosts in the same queue
❖
For jobs running from different queues on the same host
How LSF counts resources
Resources on a host are not available if they are taken by jobs that have been started, but
have not yet finished. This means running and suspended jobs count against the limits
for queues, users, hosts, projects, and processors that they are associated with.
Job slot limits
Job slot limits often correspond to the maximum number of jobs that can run at any
point in time. For example, a queue cannot start jobs if it has no job slots available, and
jobs cannot run on hosts that have no available job slots.
Resource
reservation and
backfill
When processor or memory reservation occurs, the reserved resources count against the
limits for users, queues, hosts, projects, and processors. When backfilling of parallel jobs
occurs, the backfill jobs do not count against any limits.
MultiCluster
Limits apply only to the cluster where lsb.resources is configured. If the cluster
leases hosts from another cluster, limits are enforced on those hosts as if they were local
hosts.